Tim Geithner, the last holdover from President Obama's original economic team, has indicated he's ready to go. If Obama wins, Geithner is expected to resign soon after, but Treasury officials are mum on the details.

The first big challenge for the next Treasury Secretary -- whether Obama is re-elected or Mitt Romney wins -- will be brokering a thoughtful solution to avoid the so-called fiscal cliff, a series of massive tax hikes and spending cuts slated to kick in Jan. 2. The next secretary could end up spending part of the year cleaning up the economic mess should $7 trillion worth of cuts and tax hikes take place.

OBAMA PICKS

Washington insiders' top pick is White House Budget Director Jacob "Jack" Lew, who played a key role last year in debt ceiling and deficit reduction talks. While Lew doesn't have as much international experience, he'd be a strong pick to navigate the budget drama ahead, veterans say.

Another top name mentioned is Larry Fink, CEO of BlackRock(BLK) one of the world's largest investment firms and, reportedly, a friend of Geithner's.

Other names floated include Gary Gensler, chair of the Commodity Futures Trading Commission and a Goldman Sachs(GS) veteran, and Gene Sperling, director of the National Economic Council, who was also a top economic adviser to President Clinton.

An unlikely, but often talked-about candidate is Sheila Bair, a Republican with a populist bent. However, several Washington insiders say her book about the financial crisis and recent Fortune columns have made her too many enemies in Washington.

Two more finance-side possibilities include Pimco CEO Mohamed A. El-Erian and Kenneth Chenault, the CEO of American Express(AXP).

ROMNEY PICKS

The top name that comes up for a Romney administration Treasury Secretary is Glenn Hubbard, who is now serving as the former Massachusetts governor's chief economic adviser. Hubbard was chairman of President George W. Bush's Council of Economic Advisers.

How Obama or Romney can fix the big banks

Hubbard, the dean of Columbia University's Graduate School of Business, is a leading pick for many reasons, including his background in academia, as opposed to Wall Street, which makes him easier to confirm in the Senate.

Also high on the list is former president of the World Bank Robert B. Zoellick, who served as a deputy secretary of state during the George W. Bush administration and was an international vice chairman at Goldman Sachs.

New voice

Getting a new voice at the table, even in an Obama administration, will help things, say economic policy gurus like Tony Fratto, a former senior official in President George W. Bush's Treasury Department and White House, who adds that he's a fan of Geithner.

"Geithner served his president really well," said Fratto, a partner at Hamilton Place Strategies. "But if Obama wins, it may be fortunate to have a different voice at the table, since all the other dynamics are going to be the same."

However, if the House and Senate remain politically divided, and Obama wins the electoral college but not the popular vote, the next Treasury Secretary could face an even rougher partisan road threatening the ability to get anything done.

"It depends on what kind of state the country is after the election," said Phillip Swagel, a professor of public affairs at University of Maryland, and former assistant treasury secretary in the George W. Bush administration. "If the election ends in bitterness, it'll be a tough job."